The iPhone 5's A6 processor was manufactured by rival firm Samsung, according to microscopic analysis of the iPhone's innards.

Microscopic analysis of the components inside the Apple iPhone 5 strongly suggests that the A6 chip - the central processing unit of the iPhone 5 and its single most important component - was manufactured by mobile technology rival Samsung.

Engineers at UBM TechInsights opened up the iPhone 5, levered the components out and shaved them down layer by layer, training their electron microscopes on the elements revealed each time. The die markings on the CPU, invisible to the human eye, are similar to those found on the A4 and A5 chips, which is a giveaway that this component is also Samsung's work.

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Speaking to VentureBeat, TechInsights technical research manager Allan Yogasingam explained the firm's conclusions.

“All signs point to Samsung doing the manufacturing,” he said. “Manufacturing semiconductors is like a fingerprint, as each process is unique to the fabrication facility, in this case Samsung’s 32nm process technology.”

iPhone 5 A6 processor, dissected by TechInsights

The giveaway die markings on the iPhone 5's A6 processor, suggesting it's manufactured by Samsung. Pic courtesy of TechInsights

Previous A-class processors in Apple's iOS devices have been made by Samsung, but the past year's bitter and protracted court battles between the technology giants suggested that Apple might look elsewhere when putting together the iPhone 5. But business is business, it would appear, and the rivals are working together again.

While the chip is constructed on Samsung's production line, the custom-designed A6 core is a big step for Apple, whose previous A4 and A5 processors for iPhones and iPads were based on designs adopted from ARM. After analyzing code, chip size and the architecture, experts have concluded that Apple has designed its own CPU from the ground up rather than licensing an existing processor design. Read: Apple's chip future looks bright with first custom-designed A6. Experts claim that Samsung won't be able to match the power of the new chip for three months. Read: Apple spent $500m designing custom A6 chip that is superior to anything Samsung has

Apple's self-designed A6 chip is 'laid out by hand'

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